1. Field
Embodiments relate to negative-type photoresist compositions and methods of forming a pattern using the same.
2. Description of the Related Art
Organic photosensitive materials, e.g., photoresist compositions, are materials that may be physically and/or chemically changed by light and/or radiation energy. The organic photosensitive materials may be applied to microfabrication technologies, e.g., a photolithography process, and have been used for manufacturing electronic devices, e.g., integrated circuit (IC) devices, memory devices, printed circuit boards (PCBs), microelectromechanical systems (MEMS), display devices, image display devices, etc.
A chemically amplified photoresist, which may be an organic photosensitive material, may include an acid-reactive polymer or an acid-reactive compound together with a photoacid generator. In a chemical amplification, active species generated by one photon may cause a chain reaction so that quantum yield may increase greatly. In the chemically amplified photoresist, an acid may be generated from the photoacid generator when exposed to light; and combination or decomposition of the acid-reactive polymer or the acid-reactive compound may occur by chemical action, i.e., catalyzation, of the acid.
In the chemically amplified photoresist, the acid-reactive polymer or the acid-reactive compound may not directly react by exposure to light. Rather, acid may be generated from a portion of the photoacid generator exposed to light, thereby forming a latent image. The generated acid may serve as a catalyst for the acid-reactive materials in a subsequent post-exposure bake (PEB) process. Thus, a chemical reaction may be amplified in the chemically amplified photoresist to cause a solubility difference between an exposed portion and a non-exposed portion thereof. The PEB process has been widely used for forming an image pattern using the chemically amplified photoresist.